Apparatus of this type are used, for example, although by no means exclusively, for folding bed sheets so that these can be packed ready for sale after having been sewn. Such apparatus comprise at least two transport belts which can be driven in opposite directions and are disposed such that a gap is produced between them. In order to fold the fabric length, this is laid out on the transport belts, coming to lie above the gap between the transport belts. The fabric length is drawn into the gap through the two transport belts being driven in opposite directions, so that the fabric length is folded once. More than two transport belts may be disposed one behind the other, depending on the number of times the fabric length has to be folded, with each two transport belts forming a gap for folding the fabric length. The fabric lengths can thus be folded several times in succession by driving the various transport belts accordingly.
The disadvantage of the known apparatus lies in the fact that relatively large tolerances of the alignment of the individual fabric layers occur when folding the fabric lengths. A particular result of this is that, instead of the lateral edges of the fabric lengths coming to lie in an optimum parallel position on top of one another following folding, an angular offset starting from the folding edge occurs between the lateral edges. Errors of this kind in the alignment of the edges are particularly detrimental when the fabric length is folded several times, as folding errors increase in subsequent folding stages.